As with any topological bicomplete category, there is a notion of geometric realization
for simplicial objects in \({K}/B\)  (see for example VII.3 of [1]}).
If \(X\)  is a simplicial object in \({K}/B\) , then the fiberwise geometric realization \(|X|\)  of
\(X\)  is defined by the usual coend formula:
\(|X| = \int ^{[n]\in \Delta } X_n\otimes \Delta ^n.\) 
